Abstract [en]

In recent year, the need of providing buildings with cooling has increased, especially in offices there the used electrical equipment in the form of computers, lighting and other electrical equipment. In order to chill away the heat that is given from these equipments used for current old chill machines that are owned by real-estate owners in Gävle. Instead in order to change or to fulfil these machines with environment dangerous cold mediums come the thought with providing Gävle with district chill which is a distinguished alternatives and concurrent is environmentally friendly.

The most front aim with this work has been to do temperature calculations around distribution pipes that will be placed on bottom of Gavleån without bigger complications such as isolated pipes and digging for steam disposition, and to convert an assessment if this is possible. Another aim was to do pressure case calculations on these pipes. The work is provided of SWECO-THEORELLS in Gävle, the company had already done temperature calculations, and the work was allocated also in order to compare the results.

The temperature calculations were resort to heat transfer's principles on swiftly-flowing fluid bodies, this in order that the pipes are surrounded by streaming water. The water temperature was assumed to 20ºC that is huge heavily assumption in order to last on a depth up to 6m. The conclusive temperature to the heat bills of exchange is 5.5ºC.

The pressure case calculations were done in one MICROSOFT-EXCEL document, the starting points each one previous course during the education's time that was called energy resources which facilitated calculations.

Arrived results hopefully will lie to shallow for a continued work and an execution of these planning's.

The following results have been brought about:

A temperature on 5.8ºC is received to long away located subscriber at 20ºC hot water

203 kPa pressure case on flow into, only distribution pipes

The following conclusions could be extracted:

A certain difference was detected between earlier calculations, since considerations been taken to extreme relations so decreases this difference's importance

Reduction of water flow during the summer mean one risk while spirit that does the delivery of desired temperature uncertain, special during the hottest days

That estimated available pressures will not cover the need in accordance with calculations performed in this work